Function gray_inverse 

pub fn gray_inverse(g: usize) -> usize

The inverse of gray: $g^{-1}(g) = \bigoplus_{k \ge 0} \lfloor g / 2^{k} \rfloor$.

Examples

use comnum_math::{gray, gray_inverse};
assert!((0..1024).all(|i| gray_inverse(gray(i)) == i));